PookieDo my acne cleared up with oil cleansing alone. Had it from 10 until late thirties, nothing worked for more than a short time, and my face relentlessly pumped out ridiculous amounts of oil. All the antibiotic treatments only worked for a short time, and most of the topical treatments were hideously drying, resulting in a a red, sore face (still with spots - a double whammy!) that subsequently caused my skin to ramp up the oil production even more.
Within two weeks of oil cleansing, my face was clear. The theory is that the larger molecule of oil attract the smaller sebum molecules and remove them, without drying the skin and then causing it to increase oil production even more, thus causing more acne, etc.
I don't care if there is no scientific evidence for it, it works for me where the medical treatments (presumably with evidence in their favour?) did not. And it's as cheap as chips, and doesn't cause side effects such as redness and peeling, which frankly are often as bad as the acne itself.
It may just be that no studies have been done, rather than studies have shown it to be ineffective. In any case, with any medical treatment, at an individual level there will be some it works for and some it doesn't, regardless of the overall, population-level efficacy figures in the research studies. Looking for evidence-based treatments is the best place to start, but limiting yourself only to what has been studied can result in missing out on effective treatments. This is particularly true with acne, where we still don't have treatments that are effective without major side effects.